Amazon’s Kindle for iPhone app is now available free on the Apple App Store for your download pleasure. Released in more than 60 countries, the new app allows users to take advantage of Amazon’s digital retail library over a wireless connection. Essentially, you can now grab a best-seller without going near a bookstore.

Unlike the real device, the Kindle app doesn’t support outside formats such as Adobe Acrobat PDF files. However, the Kindle for iPhone app has got one thing over its gadget cousin: it’s free, and if you were looking for an introduction to what Amazon’s Kindle is, this may well be it.

If you’ve already gotten stuck into buying Amazon digital books, you’ll find that they’re all readable on your iPhone using this app. Simply install the app, log in to your account, and the phone will grab the books. Amazon’s Whispersync technology also remembers the page you’re up to – meaning if you read a page on your iPhone on the bus, the moment you look at it on your PC at home that’s the page you’ll first go to.

Other features include the ability to change font sizes for easier reading, and add bookmarks by tapping the corner of the screen.

Aside from the iPhone & iPod Touch application, Kindle is also currently available for the Windows PC, and will soon be released for BlackBerry phones and Apple Mac computers.